mutex

Mutex that can be locked and unlocked for mutual exclusion of different processes. More...

Enumerations
enum	ua_mutex_mode { UA_MUTEX_DEFAULT = 0, UA_MUTEX_SHARED = 1 }
	Mode for a newly created mutex. More...

Functions
int	ua_mutex_init (ua_mutex_t *mutex, int mode) UA_NONNULL(1)
	Initialize a mutex in a given mode. More...
int	ua_mutex_clear (ua_mutex_t *mutex) UA_NONNULL(1)
	Clear a mutex. More...
int	ua_mutex_lock (ua_mutex_t *mutex) UA_NONNULL(1)
	Lock a mutex. More...
int	ua_mutex_unlock (ua_mutex_t *mutex) UA_NONNULL(1)
	Unlock a mutex. More...

Detailed Description

Mutex that can be locked and unlocked for mutual exclusion of different processes.

Enumeration Type Documentation

enum ua_mutex_mode

Mode for a newly created mutex.

See also

ua_mutex_init

Enumerator
UA_MUTEX_DEFAULT	Default: shared or private is platform specific.
UA_MUTEX_SHARED	Mutex can be shared by multiple processes.

Function Documentation

int ua_mutex_clear

(

ua_mutex_t *

mutex

)

Clear a mutex.

the mutex may no longer be locked or unlocked.

Parameters

mutex

Mutex to clear.

Returns

Zero on success or non-zero value on failure.

int ua_mutex_init	(	ua_mutex_t *	mutex,
		int	mode
	)

Initialize a mutex in a given mode.

The state of the mutex after initialization is unlocked.

Parameters

mutex	Mutex structure to initialize.
mode	Mode of the mutex, see ua_mutex_mode.

Returns

Zero on success or non-zero value on failure.

int ua_mutex_lock

(

ua_mutex_t *

mutex

)

Lock a mutex.

If the mutex is already locked the calling process shall be blocked until the mutex is unlocked.

Parameters

mutex

Mutex to lock.

Returns

Zero on success or non-zero value on failure.

int ua_mutex_unlock

(

ua_mutex_t *

mutex

)

Unlock a mutex.

The mutex shall only be unlocked by the process that locked it. Only a locked mutex shall be unlocked.

Parameters

mutex

Mutex to unlock.

Returns

Zero on success or non-zero value on failure.